不同严重程度支气管哮喘儿童肠道菌群差异的探索性分析

Exploratory analysis of gut microbiota differences in childhood asthma with different severity

目的·探讨不同严重程度支气管哮喘患儿肠道菌群的特征及差异,并构建重症哮喘肠道菌群预测模型。方法·选取2020年9月1日—2022年8月31日期间在复旦大学附属儿科医院呼吸科门诊就诊且主要诊断为哮喘的5~14岁儿童,根据2020年版《儿童支气管哮喘的规范化诊治建议》纳入重症哮喘儿童,根据年龄、性别匹配同期轻中度哮喘儿童、健康体检儿童。使用16S rRNA高通量测序对3组儿童新鲜粪便标本进行肠道菌群检测,比较各组儿童肠道菌群的多样性及群落结构,分析差异物种,绘制重症哮喘预测模型受试者操作特征曲线(receiver operating characteristic curve,ROC曲线)并比较曲线下面积(area under curve,AUC)。结果·共纳入重症哮喘儿童50例、性别和年龄匹配的轻中度哮喘儿童54例以及健康对照儿童39例。与健康对照组儿童相比,轻中度哮喘组和重症哮喘组儿童肠道菌群的α多样性显著降低(P<0.05)。健康对照儿童、轻中度哮喘儿童、重症哮喘儿童组密螺旋体属(Treponema)的相对丰度依次增加(P<0.001);与健康对照组儿童相比,轻中度哮喘组和重症哮喘组乳杆菌属(Lactobacillus)的相对丰度较高(均P<0.05)。重症哮喘儿童肠道菌群中普雷沃菌属(Prevotella)、乳杆菌属(Lactobacillus)、真杆菌属(Eubacterium_eligens_group)、密螺旋体属(Treponema)、纺锤链杆菌属(Fusicatenibacter)的相对丰度较高;轻中度哮喘组巴恩斯菌属(Barnesiella)、霍尔德曼菌属(Holdemanella)、罗姆布茨菌属(Romboutsia)、苏黎世杆菌属(Turicibacter)的相对丰度较高;健康对照组儿童未培养细菌(uncultured)、Muribaculaceae菌属的相对丰度较高。其中,重症哮喘患儿肠道菌群中巴恩斯菌属的相对丰度较低,其预测重症哮喘的敏感度及特异度均高于其他菌属(AUC 0.713,95%CI 0.604~0.815)。结论·哮喘患儿的肠道菌群的多样性低于健康对照儿童,且不同严重程度哮喘儿童的肠道菌群存在较多显著差异物种。其中巴恩斯菌属在重症哮喘患儿肠道菌群中丰度显著降低,提示肠道菌群分析在儿童哮喘严重程度评估中的重要价值。

Objective·To explore the characteristics and differences of gut microbiota in children with different severity of bronchial asthma,and build a prediction model of gut microbiota in severe asthma.Methods·In this study,children aged 5 to 14 diagnosed with asthma in the Department of Respiratory Medicine of Children's Hospital of Fudan University from Sep 1,2020 to Aug 31,2022 were selected,and children with severe asthma(SA)according to the Recommendations for Standardized Diagnosis and Management of Bronchial Asthma in Children(2020)were included.Children with mild to moderate asthma(MMA)and healthy children in the same period were matched according to age and gender.Stool samples collected from the three groups were subjected to 16S rRNA gene sequencing and the gut microbiota diversity,structure,and composition were assessed.The area under the receiver operating characteristic(ROC)curve(AUC)was applied to compare the predictive efficacy for SA.Results·Fifty children were enrolled in the SA group,54 children matched by gender and age were in the MMA group and 39 healthy children were in the healthy control group.Theαdiversity of gut microbiota significantly decreased in the asthma children(P<0.05),compared with that in the healthy control group.The relative abundance of Treponema was the highest in the SA group,followed by the MMA group and healthy control group(P<0.001).The relative abundance of Lactobacillus in the MMA group and SA group was higher than that in the healthy control group(both P<0.05).The SA group had a higher relative abundance of Prevotella,Lactobacillus,Eubacterium_eligens_group,Treponema,and Fusicatenibacter.The MMA group had a higher relative abundance of Barnesiella,Holdemanella,Romboutsia and Turicibacter.The healthy control group had a higher relative abundance of the uncultured and Muribaculaceae.Among them,the relative abundance of Barnesiella decreased in the SA group,and it was found to have the highest sensitivity and specificity in predicting SA(AUC 0.713,95%CI 0.604‒0.815).Conclusion·The diversity of gut microbiota in asthma children is lower than that in healthy children,and the composition of gut microbiota differs among childhood asthma with different severity.The abundance of Barnesiella decreases in the SA group significantly,suggesting that analysis of gut microbiota may help in the assessment of childhood asthma with different severity.